There are air stones specifically for O2, and there are air stones for air. The air stones for O2 aren't supposed to be used at over 40 psi., and you need to turn down the volume of O2 or you could harm the fish.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).